This invention relates generally to disk drive storage systems. In particular, the present invention is a disk drive system with a removable and exchangeable cartridge incorporating magnetic media, head and voice coil assemblies. The disk drive system includes a plurality of mechanical engagement features arranged in a triangular pattern for engaging the removable cartridge and preventing movement of the cartridge during operation of the disk drive system. The mechanical engagement features supporting adaptive magnetic and electrical engagement features which enable operation of the disk drive system.
Disk drive systems of the xe2x80x9cWinchesterxe2x80x9d type are well known in the industry. A disk drive system of this type typically includes a head disk assembly and a printed circuit board (PCB) assembly for controlling operation of various components of the head disk assembly. The head disk assembly generally includes an enclosure which houses a magnetic disk arrangement, a magnetic transducer arrangement, a rotary actuator arrangement and a spindle motor arrangement. The magnetic disk arrangement is defined by one or more rigid disks coated with a magnetizable medium for storage of digital information in a plurality of circular, concentric data tracks. The disks are driven (i.e., rotated) by the spindle motor arrangement to spin, and thereby cause the surfaces of the disks to pass under respective read and write transducers of the magnetic transducer arrangement. The read and write transducers write information to and read information from the concentric data tracks in the disk surfaces of the rigid disks. There is typically one read and write transducer for each recording surface of each rigid disk.
The rotary actuator arrangement moves the read and write transducers from track to track cross the surfaces of the rigid disks under control of circuitry. The rotary actuator arrangement typically includes a permanent-magnet arrangement, a pivot bearing cartridge and a head stack assembly. The pivot bearing cartridge includes a stationary shaft secured to the enclosure to define an axis of rotation for the head stack assembly. The head stack assembly, often referred to as an xe2x80x9cE-blockxe2x80x9d includes a flex circuit assembly, a voice coil and track accessing arms. Each one of the read and write transducers is secured to a respective one of the track accessing arms. During use, circuitry causes current to conduct through the voice coil, and because the voice coil lies in the magnetic field provided by the permanent-magnet arrangement, a torque is applied to the head stack assembly. The amount and direction of that torque is subject to control by a servo system that controls the rotary position of the read and write transducers relative to tracks on the respective recording surfaces of the rigid disks. Track accessing is limited to a certain range of disk tracks from an inner radius to an outer radius of the rigid disks by limiting the pivotal movement of the head stack assembly via a set of crash stop assemblies.
In a standard xe2x80x9cWinchesterxe2x80x9d disk drive system, all the major sub-components, including the PCB assembly, rigid disks, the head stack assembly, the read and write transducers, the permanent magnets, the spindle motor, and crash stop assemblies are all mounted onto a drive base and cover that defines the enclosure. This enclosure is sealed to provide a relatively contaminant-free interior for these sub-components. Because of the need to maintain this contaminant free environment within the enclosure, these sub-components, particularly the disks, are not readily removable from the disk drive system enclosure.
The disk drive system, which includes the enclosure and sub-components, is typically rigidly mounted to a computer system housing so as not to be removable from the computer housing and therefore, so as not to be exchangeable with other disk drive systems, even of the same type. However, there are some disk drive systems that are meant to be readily removable and exchangeable. In either case during operation it is necessary that for the disk drive system to be rigidly mounted to the computer housing in a fixed position so as to prevent any xe2x80x9cplayxe2x80x9d (i.e., movement) of the disk drive system. This xe2x80x9cplayxe2x80x9d, whether side-to-side or up-and-down, is caused by vibration as a result of operation of other systems within the computer housing and/or operation of the sub-components within the disk drive system itself. This vibration can be due to or cause undesirable imbalances in the magnetic disk arrangement because of the high rotational speeds of the rigid disks. In addition, this vibration can be due to or cause undesirable imbalances in the rotary actuator arrangement which can cause actuator tracking problems that can result in the actuator arrangement taking longer to find the desired track on a rigid disk. As such, vibration causing xe2x80x9cplayxe2x80x9d can degrade the overall performance of the disk drive assembly. Hence, for proper operation of the disk drive system, it is necessary to rigidly mount the disk drive system to prevent unwanted xe2x80x9cplayxe2x80x9d. Moreover, in the case where the disk drive system is designed to be readily removable and exchangeable, it is exceedingly necessary to rigidly secure the readily removable and exchangeable portion of the disk drive system against unwanted movement (i.e., xe2x80x9cplayxe2x80x9d) during operation of the disk drive system.
One non-readily removable and non-readily exchangeable xe2x80x9cWinchesterxe2x80x9d disk drive system as described above is disclosed in U.S. Pat. No. 4,317,146 to Gervais et al. In Gervais et al., in contrast to what is described above, a stepper motor rather than a voice coil is used to actuate the track accessing arms of the head stack assembly.
The U.S. Pat. No. 5,235,481 to Kamo et al., discloses a readily removable and exchangeable disk drive system. In Kamo et al., a separate cartridge, which houses a disk/hub assembly, a head/arm assembly with a pivot, and a polarized magnet assembly, is readily removable from its drive and exchangeable with other drives. However, in Kamo et al., the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance.
The U.S. Pat. No. 4,359,762 to Stollorz discloses a readily removable and exchangeable disk drive system. In Stollorz, a separate storage module, which houses a disk/hub assembly and a head/arm assembly, is readily removable from its drive module so as to be exchangeable with other like drive modules. In Stollorz an external linear screw translation system drives and controls the head arm assembly. However, in Stollorz, like Kamo et al., the separate storage module is not adequately rigidly secured within the drive module so as to prevent vibration causing degradation in disk drive performance.
The U.S. Pat. No. 5,214,550 to Chan discloses a readily removable and exchangeable disk drive system similar to Kamo et al. As such, like Kamo et al. and Stollorz, the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance.
The U.S. Pat. Nos. 4,974,103; 4,965,691; and 5,175,657 to Iftikar discloses a readily removable and exchangeable disk drive system. In Iftikar a separate cartridge encloses transducer heads, a disk and its spindle translator, and one or more of actuators, either voice coil or magnets. The edges of the separate cartridge are locked in position via a pair of tracks in the drive housing""s interior with the separate cartridge""s middle portion suspended in the air. The rotation of the disk spindle inside the cartridge is actuated by a rotating magnetic field generated by a fixed coil assembly distanced from the cartridge""s disk spindle. Such a rotating magnetic field not only would induce the rotation of the disk spindle, but also unwanted vertical and horizontal vibrations of the separate cartridge. These vibrations can lead to many technical problems such as recording track mis-registration, modulation and noise which are critical to high density, high performance recording. Also, a connector connecting the electronic components inside the removable cartridge to the drive base system lack essential features for preventing static electrical charges which can be very damaging to the read/write heads and the pre-amplifier chip.
The U.S. Pat. No. 5,694,267 to Morehouse et al. discloses a readily removable and exchangeable disk drive system. In Morehouse et al., a separate cartridge, which houses a disk/hub assembly, a head/arm assembly is readily removable from its drive and exchangeable with other drives. While the disk media, when not used, are mechanically enclosed inside the cartridge via a shutter system similar to a floppy disk, cartridge shuttering during loading and unloading of the cartridge can generate particles and thereby contaminate the cartridge and the head/disk interfaces. As such, when the drive operates, the disk assembly, along with the heads, are exposed to the drive environment and airflow inside the cartridge is not properly shrouded so as to prevent turbulence which can negatively affect the seeking and tracking performance of the transducer heads. In addition, the separate cartridge is not adequately rigidly secured within the drive so as to prevent vibration causing degradation in disk drive performance.
There is a need for improved disk drive systems. In particular, there is a need for a disk drive system that includes a readily removable and exchangeable magnetic disk drive cartridge, housing a disk/hub assembly and a head/arm assembly, with the disk drive cartridge being adequately rigidly secured within the drive housing so as to prevent vibration causing degradation of disk drive performance. Moreover, the disk drive cartridge should be adequately sealed to prevent contamination by particles and other contaminants that can adversely affect performance. In addition, the disk drive cartridge should prevent air turbulence which can negatively affect the seeking and tracking performance of the transducer heads.
The present invention is a magnetic storage cartridge adapted to be removably received by a disk drive assembly. The magnetic storage cartridge comprises a housing that includes at least one magnetic disk rotatable about a first axis, and an actuator arrangement pivotal about a second axis. The actuator arrangement includes at least one read/write head for reading and writing information to and from the at least one magnetic disk. The housing also includes a first engagement feature positioned on the housing at a vibration source. The first engagement feature adapted to be engaged by a first corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge.
In one aspect of the present invention, the housing further includes a second engagement feature positioned on the housing at a further vibration source. The second engagement feature is adapted to be engaged by a second corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge. The first engagement feature is coincident with the first axis and the second engagement feature is coincident with the second axis. In a further aspect of the present invention, the housing further includes a third engagement feature. The third engagement feature is adapted to be engaged by a third corresponding engagement feature of the disk drive assembly to secure the magnetic storage cartridge to the disk drive assembly and permit operation of the magnetic storage cartridge. This third engagement feature is spaced from the first and second axes. In this further aspect of the present invention, the first, second and third engagement features are arranged in a triangle.
In another embodiment, the present invention provides a magnetic storage cartridge adapted to be removably received by a disk drive assembly. The magnetic storage cartridge comprises a housing that includes at least one magnetic disk and an actuator arrangement. The magnetic disk includes information critical to operation of the magnetic storage cartridge. The actuator arrangement includes at least one read/write head for reading and writing information to and from the at least one magnetic disk. The at least one read/write head upon insertion of the magnetic storage cartridge into the disk drive assembly accesses the information critical to operation of the magnetic storage cartridge to insure proper operation of the magnetic storage cartridge.
In a further embodiment, the present invention provides a disk drive assembly for removably receiving a magnetic storage cartridge having a first major surface and an opposite second major surface. The disk drive assembly comprises a housing configured for receiving the magnetic storage cartridge. The housing includes a first member, and a second member movable relative to the first member. The first and second members have an undocked state, wherein the second member is spaced from the first member by a first distance and the magnetic storage cartridge can be inserted to and removed from the housing, and a docked state, wherein the second member has been moved towards the first member so as to be spaced from the first member by a second distance less than the first distance, and wherein the first and second members engage the first and second major surfaces of the magnetic storage cartridge to secure the magnetic storage cartridge within the housing to permit operation of the magnetic storage cartridge.
In one aspect of this further embodiment, both the first and second members are movable. These first and second members are movable linearly in a direction substantially perpendicular to the first and second major surfaces of the magnetic storage cartridge. In a further aspect of this further embodiment, the first member is linearly movable in a first direction and the second member is linearly movable in a second direction substantially perpendicular to the first direction. In still a further aspect of the present invention, the first and second members are pivotally movable.
By engaging and securing the magnetic storage cartridge at its primary sources of vibration, the readily removable and exchangeable magnetic storage cartridge is rigidly secured within the base drive housing so as to substantially minimize vibrations that may cause a degradation in disk drive performance. In particular, the upper and lower plates of the base drive engage the magnetic storage cartridge at the rotational axes of the magnetic disk and the actuator arrangement as well as a third point to ensure a stable and secure mounting arrangement for the readily removable and exchangeable magnetic storage cartridge. Moreover, this mounting arrangement helps reduce the noise level of the magnetic storage cartridge, and helps absorb undesirable heat due to the rotation of the magnetic disk by conducting this heat out of the cartridge and to the upper and lower plate members. This mounting arrangement also allows the magnetic storage cartridge to be adequately sealed to prevent contamination by particles and other contaminants that can adversely affect performance. In addition, sealing of the magnetic storage cartridge substantially minimizes air turbulence which can negatively affect the seeking and tracking performance of transducer heads. Lastly, by pre-writing operational information related to the magnetic storage cartridge to the magnetic disk, or an enclosed semiconductor memory chip, this pre-written operational information can be accessed to achieve the optimal read/write and error-rate performance particular to the magnetic storage cartridge accepted by the base drive.